"In his July 2021 essay “On the Historical Unity of Russians and Ukrainians,” Mr. Putin refers to  

Prince Volodymyr, a Viking warlord who belonged to the Rus tribe in Kyiv and who converted to Christianity in the year 988. 

 St. Vladimir of Kyiv, as the Russians came to call him, became credited with Christianizing Russia.  

Mr. Putin has argued that this ancient link between Ukraine and Russia “largely determines our affinity today,” justifying the invasion.

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